The BBC's Andrew North in Kabul says the prisoners would have had to negotiate various checkpoints to reach the perimeter.

The detention facility is said to house senior al-Qaeda suspects from countries such as Pakistan.

Col O'Hara said there were no US casualties in the escape.

The Bagram facility has proved controversial.

US soldiers there have been accused of a number of abuses of prisoners - including torture and the deaths of two inmates - sparking criticism from human rights groups and a thorough investigation by the US military.

Coalition forces check a wedding car during the manhunt

The details of the investigation were leaked to the New York Times in May.

Afghan President Hamid Karzai said he was shocked by the report and called for the guilty to be punished.

Seven US servicemen have been charged in relation to the two deaths at Bagram in 2002.

Monday's escape came as the US pledged another 700 extra troops to bolster security ahead of September's parliamentary elections.

The airborne battalion would arrive "very soon", said US military spokesman Col James Yonts.